<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    {{message}}
    <div  id="app" class="app">
        {{message}}
        <span>{{message}}</span>
    </div>
     <!-- 开发环境版本，包含了有帮助的命令行警告 -->
  <script src="https://cdn.jsdelivr.net/npm/vue/dist/vue.js"></script>
  <script>
      var app=new Vue({
          el:"#app",
          //el:".app",
          //el:"div",
          data:{
              message:"hello vue"
          }
      })
  </script>
 
</body>
</html>